This invention relates to an interruption control system for an image forming apparatus, and more particularly to an interruption control system for an apparatus which optically scans a document to form an image of the document on an image forming medium.
Known image forming apparatuses of this type are, for example, electronic copy machines, thermal transfer color copy machines, laser printers and thermal printers. The image forming apparatus is comprised of a scanning means for optically scanning a document to produce image information as optically picked up, and an image forming means for forming the image of the document on an image forming medium such as paper according to the image information derived from the scanning means.
During the image forming operation, an operator frequently encounters the need to interrupt the operation of the apparatus. To satisfy such a desire, the image forming apparatus currently used is provided with an input means for inputting, by means of a stop key, into the image forming apparatus a stop signal to interruptively stop the apparatus during its operation. In such an interrupted operation, the paper which is in the process of forming an image is automatically fed to the outside of the machine, regardless of its image forming state. Therefore, the paper having no image formed thereon as well as the paper having an image imperfectly formed due to the interruption, is discharged to the outside of the apparatus. Therefore, the paper is wasted.
Of those image forming apparatuses, the apparatus for forming multicolor images, such as the thermal transfer color copy machine, particularly suffers from another problem. A jam tends to occur during the course of the paper being discharged during an interruption. This arises from the fact that the paper transfer path of the multicolor image forming apparatus is more complicated in structure than that of the monocolor apparatus.